House Minority Leader Nancy Pelosi has disappointed some of her liberal base with her defense of the Obama administration's classified surveillance of U.S. residents' phone and Internet records.

The San Jose Mercury News reported that some of the activists attending the annual Netroots Nation political conference Saturday booed and interrupted the San Francisco Democrat when she commented on the surveillance programs carried out by the National Security Agency and revealed by a former contractor, Edward Snowden.

The boos came when Pelosi said that Snowden had violated the law and that the government needed to strike a balance between security and privacy.

An activist, identified by the Mercury News as Mac Perkel of Gilroy, Calif., stood up and tried to interrupt her, prompting security guards to escort him out of the convention hall. Several others walked out in his support.